Abstract: In the epoxy ejection gun disclosed herein, a bridge member which couples and drives a pair of push rods includes a forward facing seat or socket, e.g. of conical shape. A lead nut engageable with a rotatable lead screw is provided with a surface matching the seat. An adjustable spring is provided for biasing the interfitting parts. Rotation of the lead screw causes the lead nut to advance driving the push rods but pressure is controlled by the selected value of biasing force on the matching surfaces, excessive force allowing the lead nut to rotate with the lead screw rather than to advance.

Abstract: In the caulking gun disclosed herein, the piston of a caulking cartridge is driven by axial movement of a exteriorly threaded tube which is, in turn, driven by a rotating ring gear which is interiorly threaded to mate with the tube. The threaded tube is longitudinally split so that it can collapse out of engagement with the threads on the ring gear. A tapered plug cooperates with an expandable bushing inside the tube so as to hold the tube in engagement with the threads in the ring gear when the plug is in a first postion but, when the plug is moved to a second position, the bushing allows the tube to collapse thereby releasing pressure from the piston and allowing quick retraction of the split tube to facilitate loading of a new caulking cartridge.

Abstract: The mortar dispenser disclosed herein utilizes a rotating auger extending through a feed barrel at the bottom of a supply hopper to force mortar through a nozzle attached to the barrel for use in tuck pointing. Formation of a rotating plug which would obstruct flow is prevented by an auger construction in which a single helical flute divides into a pair of flutes which, in the nozzle region, extend in opposite directions from the auger axis to provide two channels. The pair of flutes are apertured to permit mortar flow between the two channels and a slender elongate spring scraper prevents mortar from sticking to the nozzle. An agitator extending into the hopper is driven by a cam rotating with the auger so as to work mortar in the hopper and cause it to flow into the auger.